Merge tag 'iommu-v4.15-rc1' of git://github.com/awilliam/linux-vfio
[sfrench/cifs-2.6.git] / drivers / mailbox / qcom-apcs-ipc-mailbox.c
1 /*
2  * Copyright (c) 2017, Linaro Ltd
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License version 2 and
6  * only version 2 as published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it will be useful,
9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
11  * GNU General Public License for more details.
12  */
13
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/io.h>
17 #include <linux/slab.h>
18 #include <linux/of.h>
19 #include <linux/of_platform.h>
20 #include <linux/platform_device.h>
21 #include <linux/mailbox_controller.h>
22
23 #define QCOM_APCS_IPC_BITS      32
24
25 struct qcom_apcs_ipc {
26         struct mbox_controller mbox;
27         struct mbox_chan mbox_chans[QCOM_APCS_IPC_BITS];
28
29         void __iomem *reg;
30         unsigned long offset;
31 };
32
33 static int qcom_apcs_ipc_send_data(struct mbox_chan *chan, void *data)
34 {
35         struct qcom_apcs_ipc *apcs = container_of(chan->mbox,
36                                                   struct qcom_apcs_ipc, mbox);
37         unsigned long idx = (unsigned long)chan->con_priv;
38
39         writel(BIT(idx), apcs->reg);
40
41         return 0;
42 }
43
44 static const struct mbox_chan_ops qcom_apcs_ipc_ops = {
45         .send_data = qcom_apcs_ipc_send_data,
46 };
47
48 static int qcom_apcs_ipc_probe(struct platform_device *pdev)
49 {
50         struct qcom_apcs_ipc *apcs;
51         struct resource *res;
52         unsigned long offset;
53         void __iomem *base;
54         unsigned long i;
55         int ret;
56
57         apcs = devm_kzalloc(&pdev->dev, sizeof(*apcs), GFP_KERNEL);
58         if (!apcs)
59                 return -ENOMEM;
60
61         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
62         base = devm_ioremap_resource(&pdev->dev, res);
63         if (IS_ERR(base))
64                 return PTR_ERR(base);
65
66         offset = (unsigned long)of_device_get_match_data(&pdev->dev);
67
68         apcs->reg = base + offset;
69
70         /* Initialize channel identifiers */
71         for (i = 0; i < ARRAY_SIZE(apcs->mbox_chans); i++)
72                 apcs->mbox_chans[i].con_priv = (void *)i;
73
74         apcs->mbox.dev = &pdev->dev;
75         apcs->mbox.ops = &qcom_apcs_ipc_ops;
76         apcs->mbox.chans = apcs->mbox_chans;
77         apcs->mbox.num_chans = ARRAY_SIZE(apcs->mbox_chans);
78
79         ret = mbox_controller_register(&apcs->mbox);
80         if (ret) {
81                 dev_err(&pdev->dev, "failed to register APCS IPC controller\n");
82                 return ret;
83         }
84
85         platform_set_drvdata(pdev, apcs);
86
87         return 0;
88 }
89
90 static int qcom_apcs_ipc_remove(struct platform_device *pdev)
91 {
92         struct qcom_apcs_ipc *apcs = platform_get_drvdata(pdev);
93
94         mbox_controller_unregister(&apcs->mbox);
95
96         return 0;
97 }
98
99 /* .data is the offset of the ipc register within the global block */
100 static const struct of_device_id qcom_apcs_ipc_of_match[] = {
101         { .compatible = "qcom,msm8916-apcs-kpss-global", .data = (void *)8 },
102         { .compatible = "qcom,msm8996-apcs-hmss-global", .data = (void *)16 },
103         {}
104 };
105 MODULE_DEVICE_TABLE(of, qcom_apcs_ipc_of_match);
106
107 static struct platform_driver qcom_apcs_ipc_driver = {
108         .probe = qcom_apcs_ipc_probe,
109         .remove = qcom_apcs_ipc_remove,
110         .driver = {
111                 .name = "qcom_apcs_ipc",
112                 .of_match_table = qcom_apcs_ipc_of_match,
113         },
114 };
115
116 static int __init qcom_apcs_ipc_init(void)
117 {
118         return platform_driver_register(&qcom_apcs_ipc_driver);
119 }
120 postcore_initcall(qcom_apcs_ipc_init);
121
122 static void __exit qcom_apcs_ipc_exit(void)
123 {
124         platform_driver_unregister(&qcom_apcs_ipc_driver);
125 }
126 module_exit(qcom_apcs_ipc_exit);
127
128 MODULE_LICENSE("GPL v2");
129 MODULE_DESCRIPTION("Qualcomm APCS IPC driver");